Add Gateway For Mesh section to the GEP template (#3577)

* Add Gateway For Mesh section to the GEP template

* Update index.md

* Apply suggestions from code review

Co-authored-by: Mattia Lavacca <[email protected]>

---------

Co-authored-by: Mattia Lavacca <[email protected]>

Author: LiorLieberman

geps/gep-696/index.md

@@ -24,15 +24,22 @@ the content into the GEP as online documents are easier to lose
 -- e.g. owner messes up the permissions, accidental deletion)
 
 ## API
-
 (... details, can point to PR with changes)
 
+### Gateway for Ingress (North/South)
+(Include API details for North/South usecases)
+
+### Gateway For Mesh (East/West)
+(Include East/West API considerations, examples, and if different - APIs)
+
 ## Conformance Details
 
 (from https://github.com/kubernetes-sigs/gateway-api/blob/main/geps/gep-2162/index.md#standardize-features-and-conformance-tests-names)
 
 #### Feature Names
 
+(Does it require separate feature(s) for mesh? Please add them if necessary)
+
 Every feature should:
 
 1. Start with the resource name. i.e HTTPRouteXXX
@@ -49,6 +56,8 @@ Treat this guidance as "best effort" because we might have test files that check
 
 In any case, the conformance tests file names should be meaningful and easy to understand.
 
+(Make sure to also include conformance tests that cover mesh)
+
 ## Alternatives
 
 (List other design alternatives and why we did not go in that